Thin layer glass for heat exchangers

Glass-lined heat exchangers are very well suited as vaporisers, condensers and for liquid/liquid heat exchange applications. New technical features – such as the reduced layer thicknesses and connections without seals between tube plates and tube ends – provide the opportunity to use this kind of heat exchanger as an element in a glass-lined system.

Due to a big volume design, big cross sections, heavy weight and ultimately being very expensive, glass-lined heat exchangers, so far, were not really an alternative to metallic versions. A compact and sealless tube bundle heat ex-changer with a glass-lined housing eliminates those disadvantages and closes the gap between reactor, column and vessel, made of glass-lined steel. It now provides a full concept of only glass-lined mate-rials used, whenever corrosion resistance is needed during the manufacturing process. Furthermore all quality problems possibly resulting from welding, impu-rities embedded in the steel and various sealing methods have been eliminated.

Before the process of joining, the ends of the U-tubes and the bottom plate will be prepared mechanically. The connection is liquid- and gas-tight, and meets the
highest pressure requirements. The as-sembly is realised with a temperature difference of minus 160 °C between tube end and bottom hole, so that the parts will be fixed by surface pressure. The verification of tightness for glass-lined heat exchangers is done by a helium leak test.
Based on past experience the results reach values between 10-5 and 10-6 bar. At the same time a static friction strength of up to 20,000 N between tube and tube plate is realized, which gives a high guarantee against product contamination.

If required the connection can be separated without damage – this way single tube segments can be replaced individually. The connection system does meet the requirements for GMP-certified de-signs, fully.

Due to this concept product residues and product contaminations are nearly im-possible. The glass-lined tubes are
suitable for use in pressure vessels and – as a result of the described properties – can be increased up to the yield point. Experiences with this kind of heat exchangers reach up to 230 °C.
Depending on the required space a vertical or horizontal installation as a compact heat exchanger is also possible.

In order to correctly size and specify the THALEMAIL compact heat exchangers we need information on the media, as well as the material flows and temperatures.